Fence Calculator
The Fence Calculator estimates how many posts and rails you need based on your total fence length and post spacing, plus an estimate of concrete bags for setting posts. Enter lengths in feet or meters. Because the section count always rounds up (never down), your actual post spacing ends up slightly tighter than the value you enter — for example, 100 ft of fence at an 8 ft target becomes 13 sections of about 7.7 ft each rather than one full-length gap. The concrete estimate (2 bags per post hole) assumes a standard 60 lb bag and typical residential post depth; taller privacy fences or heavier gate posts set in deeper, wider holes may need 3 or more bags per post. Gates add one extra post to frame the opening but don't change the section or rail count, since a gate opening simply replaces one fence section rather than adding to it.
Switch between U.S. Customary and Metric units.
How This Tool Works
Pick your units, then enter your total fence length, desired post spacing, and number of gates to see exactly how many posts, rails, and concrete bags to buy.
Formula & Method
Sections = fence length ÷ post spacing (rounded up). Posts = sections + 1, plus one extra per gate. Rails = sections × rails per section. Concrete bags = posts × 2. Lengths can be entered in feet or meters.
Example Calculation
A 150 ft fence with posts every 10 ft and 1 gate: sections = 150 ÷ 10 = 15. Posts = 15 sections + 1 + 1 (for the gate) = 17. Rails (at 2 per section) = 15 × 2 = 30. Concrete = 17 posts × 2 bags = 34 bags. In metric, a 45 m fence with posts every 2 m and 0 gates: sections = 45 ÷ 2 = 22.5, rounded up to 23. Posts = 23 + 1 = 24. Rails (at the default 3 per section) = 23 × 3 = 69. Concrete = 24 × 2 = 48 bags.
Frequently Asked Questions
How far apart should fence posts be?+
Most residential fences use 6–8 ft (about 1.8–2.4 m) post spacing. Taller or heavier fence panels may need closer spacing for stability.
How much concrete per fence post?+
A typical post hole takes about 2 bags of 60 lb (27 kg) concrete, though larger posts or deeper holes may need more.
Can I enter fence length in meters?+
Yes — switch the unit toggle to Metric and enter your fence length and post spacing in meters. Post, rail, and concrete counts are unaffected by the unit choice.
Does this include the gate itself?+
No, this estimates structural posts and rails only. Gate hardware and the gate panel should be purchased separately based on the gate width.
Why do I get one more post than the number of sections?+
Posts sit at both ends of every section, so a fence line always needs one more post than it has sections — 13 sections require 14 posts. Each gate opening adds one additional post beyond that to frame the gate.
What happens if my fence length doesn't divide evenly by the post spacing?+
The calculator rounds the section count up to the next whole number rather than leaving a leftover gap, which slightly shortens your real spacing. For example, 100 ft at an 8 ft target becomes 13 sections of about 7.7 ft each instead of 12 full sections plus a 4 ft remainder.
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<a href="https://everyfix.net/tools/fence-calculator/">Fence Calculator</a> by <a href="https://everyfix.net">EveryFix</a>Related Tools
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